The flotation units don’t come cheap. Andy Vendetti, president of the Bristol, Pennsylvania, company High-Tech Floatation, one of three builders in the United States, says a handcrafted tub and custom enclosure like the combination he installed for Zeiger in New York costs about $25,000. Preparing the surrounding room, water heater, filtration system, and other necessary extras could easily tack on another $10,000.

In London, the Floatworks draws 1,200 customers every month to its nine-tank center, billed as the largest in the world. Sales and marketing director Simon Blake says the center will soon debut a futuristic tank design and hopes to open a second location in the city.

Blake also says he’s gaining traction with corporate human-resources departments about using the Floatworks as an antidote for stressed-out employees, and is in talks with the United Kingdom’s Blood Pressure Association about flotation’s potential for reducing hypertension. An Olympic triple-jumper who found relief from a cracked disc at the center could become the ultimate celebrity endorser should he win gold in Beijing this summer.

Even without Olympic-size aches or work-induced stress, business travelers far from home may appreciate another benefit Blake swears by. “When you suffer from jet lag, one hour of floating can be like four to six hours of sleep,” he says. “It’s all about resetting your body clock.”

Manufacturers of the tanks say that, in addition to using them at commercial centers, individuals are also buying units. Lee Perry, longtime owner of the Samadhi Tank Company in Grass Valley, California, says demand for her company’s freestanding $7,300 flotation tanks is surging. Though she won’t provide specifics, she says her roster of both individual and commercial clients is longer than it’s been in years. “Suddenly, I’m getting emails from Alabama and Georgia. Places that we’ve never ever heard from before are showing interest.”

Perhaps, she muses, the omnipresence of information and popular culture is driving people to escape from all the light and noise. “When we first started, we never, ever said, ‘sensory deprivation,’ because those words were enough to turn people away,” Perry says. Now, many of her customers crave it.